SmoothStreaming TTML fMP4 crashes player

[icetronics]

Issue description

After enabling the subtitle track during encrypted playback, the player crashes.
Setup: SmoothStreaming with PlayReady DRM, TTML in fMP4 (not encrypted)
Comparison: DRM-free SmoothStr with same subtitle setup plays flawlessly.

Link to test content

Manifest URL sent via email.
Might not be possible to play as the DRM license request requires a special header which includes an OAuth token that expires after a time.

Version of ExoPlayer being used

2.9.2

Device(s) and version(s) of Android being used

FireTV (any generation)
FireOS 5.2.6.8

A full bug report captured from the device

Sent via email.

java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.exoplayer2.util.ParsableByteArray.readBytes(byte[], int, int)' on a null object reference
        at com.google.android.exoplayer2.source.SampleQueue.sampleData(SampleQueue.java:561)
        at com.google.android.exoplayer2.source.chunk.ChunkExtractorWrapper$BindingTrackOutput.sampleData(ChunkExtractorWrapper.java:206)

[ojw28]

This is related to confusion around how subtitles are handled in DRM protected SmoothStreaming. An attempt was made to assume they're always unprotected in #4838 (which is the case in the sample provided). But it looks like the solution for doing so wasn't quite complete. It's easy to fix; we'll use this issue for tracking.

[ojw28]

Fixed in dev-v2. Please verify if you have a chance.

[icetronics]

Thanks a lot for the quick action, @ojw28! I'll try to verify it this week and get back to you. Can you please forecast which version could incorporate this fix?

[ojw28]

It'll be in 2.9.4.

[icetronics]

Hi @ojw28, just came back to let you know that your fix is working marvelously. Many thanks for the prompt action!

[ojw28]

Glad to hear it; thanks for confirming!